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Salmonella is a Gram-negative, non-spore-forming, motile, facultative anaerobic rod. The most studied species are Salmonella typhi and paratyphi (causing typhoid fever) and non-typhi Salmonella species (which can cause different clinical syndromes - gastroenteritis, disseminated infections, etc.). A 61-year-old male patient with multiple comorbidities (including myelofibrosis) presented to the Pulmonology outpatient department, Clinical County Hospital of Târgu Mureș, with a mucopurulent nocturnal cough. Paraclinical examinations showed the presence of a pleural empyema, which was evacuated in local anesthesia. The pleural fluid was sent to the Microbiology Department for bacteriological testing, where a fluoroquinolone-resistant strain of Salmonella spp. was detected. The patient received antibiotic treatment according to the antibiotic susceptibility testing. Due to the persistence of the symptoms, the patient returned two weeks later, when another puncture was performed. Salmonella was isolated again, but the strain showed a higher resistance to antibiotics. The two strains were compared using molecular methods of diagnosis (Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction - ERIC-PCR), the results showing a similarity of 92%. The occurrence of an extra amplicon band in ERIC-PCR suggests an important change in the bacterial genetic material, potentially related to acquisition of antibiotic resistance factors.

Introduction: Lately, nanotechnology focuses on the green synthesis of AgNPs, using different plant materials, as this method is accessible, cost-efficient, and ecological. The study aimed to investigate the antibacterial potential of AgNPs synthesized using beech/spruce bark extracts (BBE/SBE) and silver salts (acetate/nitrate).

Background: Sepsis is the leading cause of morbidity and mortality in intensive care units. This study explored the possible role of vascular endothelial growth factor-C (VEGF-C) and podoplanin (PDPN) in sepsis.

Following the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, design, development, validation, verification and implementation of diagnostic tests were actively addressed by a large number of diagnostic test manufacturers. This paper deals with the biases and sources of variation which influence the accuracy of diagnostic tests, including calculating and interpreting test characteristics, defining what is meant by test accuracy, understanding the basic study design for evaluating test accuracy, understanding the meaning of Sensitivity, Specificity, Positive Predictive Value and Negative Predictive Value, and evaluating them numerically, and the ROC curve (or Receiver Operating Characteristic ) and the Area under the Curve (AUC).

Lower respiratory tract secretions (LRTS) like sputum and tracheal aspirates are frequently sent to the microbiology laboratory from patients with various respiratory pathologies. Improper collection techniques can lead to false-positive results, resulting in improper therapy.

Background: Prunella vulgaris L., known as self-healing herb, is a widely spread species in the spontaneous flora with beneficial effects on human health, a fact proven in particular by Asian researchers. The aim of this study was to evaluate the antitumor activity and the antibacterial effect on different bacterial strains, including multidrug-resistant ones, depending on the type of solvent used (aqueous, hydroalcoholic), the plant product taken into consideration (spike inflorescence, leaf), its quantity and the concentration of active principles.

Snake venoms are aqueous solutions containing peptides and proteins with various biochemical, physiological, and pathophysiological effects. Several snake venom components are used as lead molecules in the development of new active substances for the treatment of cardiovascular diseases, clotting disorders, cancer or pain.

Alcohol based solutions are among the most convenient and wide spread aid in the prevention of nosocomial infections. The current study followed the efficacy of several types and isomers of alcohols on different bacterial species. Seven alcohols (ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl alcohol, and ethylene glycol) were used to evaluate their minimal inhibitory and bactericidal effects by microdilution method on bacteria that express many phenotypical characteristics: different cell-wall structure (Gram positive/negative bacteria), capsule production (Klebsiella pneumoniae), antibiotic resistance (MRSA vs MSSA) or high environmental adaptability (Pseudomonas aeruginosa). Results: The best inhibitory effect was noticed for n-propyl, followed by iso-propyl, n-butyl, and iso-butyl alcohols with equal values. Ethylene glycol was the most inefficient alcohol on all bacteria. In K. pneumoniae and P. aeruginosa, the bactericidal concentrations were higher than the inhibitory one, and to a level similar to that encountered for most of the Gram-positive bacteria. Among Gram-positive cocci, E. faecalis presented the lowest susceptibility to alcohols. Conclusions: All alcohols presented good effect on bacteria, even in low concentrations. Compared to ethanol as standard, there are better alternatives that can be used as antimicrobials, namely longer-chain alcohols such as propyl or butyric alcohols and their iso- isomers. Ethylene glycol should be avoided, due to its toxicity hazard and low antimicrobial efficacy. Bacterial phenotype (highly adaptable bacteria, biofilm formation) and structure (cell wall structure, presence of capsule) may drastically affect the responsiveness to the antimicrobial activity of alcohols, leading to higher bactericidal than inhibitory concentrations.

Background: Candida, and especially Candida albicans, colonizes the oral mucosa and becomes invasive when the immune system weakens. Therefore, frequently, oral and maxillofacial pathology can be associated with Candida. Objective: The qualitative and quantitative assessment of Candida colonization of the oral cavity in patients with oro-maxillo-facial conditions; to establish an association between the different contributing factors and colonization. Material and methods: Samples were collected from 70 patients hospitalized in the Clinic of Oral and Maxillo-Facial Surgery, by rinsing the mouth with sterile saline; historical data were also collected. The samples were analyzed at the Microbiology Laboratory of the University of Medicine and Pharmacy of Tîrgu Mureș, using Sabouraud agar medium. For each isolate, the antifungigram for Fluconazole and Voriconazole was performed following the CLSI standards. Results: From the 70 samples 45.7% were positive for 11 different yeast species. Regarding predisposing factors, most importantly, smoking was significantly associated with Candida colonization (OR = 2.34; 95% CI = 1.42-3.84; p

Objective: To evaluate the bacteriological features in non-struvite nephrolithiasis and in its associated urinary tract infection, and to establish the relationship between the two pathologies.

Pentru a avea succes în experimentele de biologie moleculară, sunt necesare cunoștințe bune despre diversele metode și protocoale în acest domeniu. În biologia moleculară, manipularea corespunzătoare a acizilor nucleici este esențială, începând cu calitatea extracției până la testele efective (PCR, RT-PCR, qPCR, PCR array, clonare, etc). Deși multe dintre protocoale sunt “standardizate”, în practică sunt multe variabile care pot influența rezultatele experimentelor. Datorită importanței proiectării corecte a primerilor în metodele de tip PCR, ne vom concentra pe modul de proiectare și pe verificarea lor cu ajutorul programelor de calculator, dar de asemenea prezentăm și alte programe utile disponibile gratuit, care pot ajuta cercetătorii în domeniul biologiei moleculare

This study aimed to synthesize palladium nanoparticles (PdNPs) using bioactive compounds from aqueous extracts of Quercus species (Quercus dalechampii, Quercus frainetto, and Quercus petraea) with potential biomedical applications. To optimize PdNPs biosynthesis, various parameters were explored, including the concentration of PdCl2, the extract-to-PdCl2 ratio, and the pH of the solution. The nanoparticles were characterized using ultraviolet/visible spectroscopy (UV/Vis), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). Total polyphenol content was measured using the Folin–Ciocâlteu method, while antioxidant capacity was evaluated through radical neutralization assays, including ABTS and DPPH, and through iron and copper reduction tests. Antimicrobial activity was tested against Gram-positive and Gram-negative bacteria, as well as Candida species. Phenolic compounds and flavonoids from the extracts were essential for the reduction in palladium ions and the stabilization of the nanoparticles. UV/Vis spectroscopy showed a distinct surface plasmon resonance peak, indicating the successful formation of PdNPs. FTIR analysis confirmed the interaction between the bioactive compounds and PdNPs, revealing characteristic peaks of phenolic groups. DLS analysis indicated a hydrodynamic diameter of 63.9 nm for QD-PdNPs, 48 nm for QF-PdNPs, and 63.1 nm for QP-PdNPs, highlighting good dispersion and stability in solution. Although the PdNPs did not exhibit strong antioxidant properties, they demonstrated selective antimicrobial activity, especially against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). PdNPs also exhibited significant antifungal activity against Candida krusei, with a minimum inhibitory concentration (MIC) of 0.63 mg/mL, indicating their ability to compromise fungal cell integrity. This study contributes to developing eco-friendly biosynthesis methods for metallic nanoparticles and underscores the potential of PdNPs in various applications, including in the biomedical field. [ABSTRACT FROM AUTHOR]

Introduction Intercellular communication helps regulate the cell density and the virulence traits in yeasts and bacteria. The study aims to identify the effects of quorum sensing molecules (QSMs) like farnesol and tyrosol on Candida spp. virulence traits. Methods The effects of farnesol and tyrosol were studied on the growth rate of Candida albicans, Candida parapsilosis, Candida krusei, Candida auris, and Candida guilliermondii at different time points, on a 48 hours incubation period. The growth rate was assessed spectrophotometrically. The biofilm formation abilities of Candida spp. were assessed by crystal violet staining technique. Moreover, the expression of C. albicans virulence genes (ALS3, HSP70, SAP2) was analyzed as a response to 100 µM farnesol and tyrosol, by RT-PCR. Results Generally, farnesol was found to inhibit the growth rate and biofilm formation mostly in non-albicans species, while tyrosol exerted a non-consistent response on the different Candida species. The expression of ALS3 and HSP70 in C. albicans was upregulated by the QSMs. Conclusions Both farnesol and tyrosol are involved in the regulation of Candida spp. virulence mechanisms, dependent on the used concentration and exposure time and in a species-dependent manner. [ABSTRACT FROM AUTHOR]

Background: The outbreak of the COVID-19 pandemic caught healthcare systems in many countries unprepared. Shortages of personnel, medicines, disinfectants, and intensive care unit (ICU) capacities, combined with inadvertent use of antibiotics and emergence of drug-resistant secondary infections, led to a surge in COVID-19-related mortality. Objective: We aimed to evaluate the prevalence of secondary bacterial infections and the associated antibiotic resistance in a temporary established ICU dedicated to COVID-19 patients. We also assessed the utility of clinical and routine laboratory data as predictors of secondary infections and mortality in these patients. Methods: We examined the medical records of 243 patients admitted to the COVID-19 Medical Support Unit of Târgu Mures, Romania, between 1 August 2020 and 31 January 2021. Results: Among the 243 patients admitted to the COVID-19 Medical Support Unit of Târgu Mures between 1 August 2020 and 31 January 2021, 59 (24.3%) presented secondary infections. Acinetobacter baumannii and Klebsiella pneumoniae were the most frequent isolates (31.1% and 18.9%, respectively), most of them multidrug resistant. Chronic obstructive pulmonary disease had a higher prevalence in patients who developed secondary infections (p = 0.012). Secondary infections were associated with longer stay in the ICU and with higher mortality (p = 0.006 and p = 0.038, respectively). Conclusions: Early identification of secondary infections and proper use of antibiotics are necessary to limit the spread of multidrug-resistant microorganisms in COVID-19 patients admitted in the ICU. [ABSTRACT FROM AUTHOR]

Oak bark, which is commonly used in the wood industry, has by-products often repurposed as fuel. Its extracts are rich in compounds with anticancer, antibacterial, antifungal, and anti-inflammatory properties. This study synthesized platinum nanoparticles (PtNPs) using aqueous extracts from Quercus dalechampii (QD), Q. frainetto (QF), and Q. petraea (QP). Key factors during nanoparticle formation included reaction time, metal ion concentration, pH, extract-to-metal ion ratio, and temperature. The PtNPs were characterized by dynamic light scattering, Fourier transform infrared spectroscopy, and transmission electron microscopy. The average diameters were 58.5 ± 7.6 nm for QD-PtNPs, 41.6 ± 5.4 nm for QF-PtNPs, and 41 ± 5.3 nm for QP-PtNPs. Antioxidant and antimicrobial activities were also analyzed. The QP-PtNPs had the highest DPPH (2,2-Diphenyl- 1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), and CUPRAC (Cupric Reducing Antioxidant Capacity) free radical scavenging activities, while QD-PtNPs excelled in ABTS (2,2'-azinobis-(3- ethylbenzothiazoline-6-sulfonic acid)) scavenging. All PtNPs showed strong antimicrobial properties, particularly against Enterococcus faecalis, Escherichia coli, Candida krusei, and Candida auris. These findings suggest that Quercus-mediated PtNPs have significant potential for developing treatments against bacterial and fungal infections, with promising applications in medicine. [ABSTRACT FROM AUTHOR]

With approximately half a billion events per year, lower respiratory tract infections (LRTIs) represent a major challenge for the global public health. Among LRTI cases, those caused by Gram-negative bacteria (GNB) are associated with a poorer prognostic. Standard-of-care etiologic diagnostics is lengthy and difficult to establish, with more than half of cases remaining microbiologically undocumented. Recently, syndromic molecular diagnostic panels became available, enabling simultaneous detection of tens of pathogen-related and antimicrobial-resistance genetic markers within a few hours. In this narrative review, we summarize the available data on the performance of molecular diagnostics in GNB pneumonia, highlighting the main strengths and limitations of these assays, as well as the main factors influencing their clinical utility. We searched MEDLINE and Web of Science databases for relevant English-language articles. Molecular assays have higher analytical sensitivity than cultural methods, and show good agreement with standard-of-care diagnostics regarding detection of respiratory pathogens, including GNB, and identification of frequent patterns of resistance to antibiotics. Clinical trials reported encouraging results on the usefulness of molecular assays in antibiotic stewardship. By providing early information on the presence of pathogens and their probable resistance phenotypes, these assays assist in the choice of targeted therapy, in shortening the time from sample collection to appropriate antimicrobial treatment, and in reducing unnecessary antibiotic use. [ABSTRACT FROM AUTHOR]

(1) Background: Carbapenem-resistant (CR) bacteria pose a significant global public health challenge due to their ability to evade treatment with beta-lactam antibiotics, including carbapenems. This study investigates the biofilm-forming capabilities of CR clinical bacterial isolates and examines the impact of serum on biofilm formation. Additionally, the study evaluates the resistance profiles and genetic markers for carbapenemase production. (2) Methods: Bacterial isolates were collected from the microbiology laboratory of Mures County Clinical Hospital between October 2022 and September 2023. Pharyngeal and rectal swabs were screened for carbapenem-resistant bacteria using selective media. Lower respiratory tract samples were also analyzed for CR Gram-negative bacteria. The isolates were tested for their ability to form biofilms in the presence and absence of fetal bovine serum at 24 and 48 h. Carbapenemase production was detected phenotypically and confirmed via PCR for relevant genes. (3) Results: Out of 846 screened samples, 4.25% from pharyngeal swabs and 6.38% from rectal swabs tested positive for CR bacteria. Acinetobacter baumannii and Klebsiella pneumoniae were the most common species isolated. Biofilm formation varied significantly between clinical isolates and standard strains, with clinical isolates generally showing higher biofilm production. The presence of serum had no significant effect on biofilm formation in Klebsiella spp., but stimulated biofilm formation for Acinetobacter spp. Carbapenemase genes blaKPC, blaOXA-48-like, and blaNDM were detected in various isolates, predominantly in Klebsiella spp., but were not the main determinants of carbapenem resistance, at least in screening isolates. (4) Conclusions: This study highlights the variability in biofilm formation among CR clinical isolates and underscores the differences between the bacteria found as carriage versus infection. Both bacterial species and environmental factors variably influence biofilm formation. These insights are crucial for the development of effective treatment and infection control strategies in clinical settings. [ABSTRACT FROM AUTHOR]

Quercus species are utilized for their durable wood, providing sustenance for wildlife, conserving biodiversity, and contributing ecological, medicinal, and esthetic benefits to ecosystems and landscapes. In this study, we aimed to use the bark of three Quercus species (Q. dalechampi, Q. fraineto, and Q. petraea) for the synthesis of silver and gold nanoparticles (AgNPs and AuNPs). The aqueous extracts from the bark of Quercus sp. acted both as reducing and stabilizing agent, facilitating the rapid synthesis of AuNPs (AuQD, AuQF, and AuQP) and AgNPs (AgQD, AgQF, and AgQP). The obtained nanoparticles were characterized using UV-vis spectroscopy, TEM, DLS, and FTIR. Characterizations revealed that the nanoparticles exhibited a variety of shapes, such as polygonal, triangular, and spherical forms, with sizes ranging between 14 and 24 nm for AuNPs and 45–70 nm for AgNPs. The total phenolic content was assessed through spectroscopic methods, while several individual phenolic compounds were identified and quantified using UPLC-PDA. Furthermore, we assessed the antioxidant, antibacterial, and antifungal capacities of AuNPs, AgNPs, and raw extracts. The highest antioxidant activity was observed for raw extracts, followed by AgNPs and AuNPs, while the most potent antibacterial and antifungal activity was observed in AgQP. Moreover, cytotoxicity was examined in a human keratinocyte cell line (HaCaT). The results indicated no cytotoxic effects for AuNPs, while AgNPs and the raw extracts exhibited cytotoxic effects after 48 h of incubation. This research underscores the multifaceted utility of Quercus bark extracts in the green synthesis of metallic nanoparticles and their subsequent bioactivity assessment, suggesting promising perspectives for their application in various fields while urging cautious consideration of their cytotoxic implications. [ABSTRACT FROM AUTHOR]

Introduction: Lower respiratory tract infections, including COVID-19, have a substantial global impact, making the development of diagnostic tests crucial. The study aimed to develop a new, accurate, fast, and cost-effective PCR-based detection method for SARS-CoV-2, applicable in limited settings and capable of detecting all current variants and potential future pathogens. Methods: The study was conducted between 2020 and 2022 at the molecular biology department of Mures County Clinical Hospital (MCCH), Romania. Initially, pharyngeal and nasal secretions were collected and processed using the real-time qRT-PCR method for routine COVID-19 diagnosis. Ninety-two samples were randomly selected to develop the assay, including samples from different infection periods and negative controls. Complementary DNA was prepared from the selected samples, and the presence and integrity of the extracted RNA were evaluated by amplifying the GAPDH housekeeping gene. Primers for three specific viral genes (N, ORF1ab, and S) were designed, and their efficiency was evaluated using endpoint PCR and sequencing. Finally, the method was optimized and implemented as a one-step triplex PCR assay for routine diagnostic use. Results: The molecular laboratory at the MCCH analyzed a total of 41,818 samples between June 2020 and December 2022. Among these samples, 26.15% tested positive for SARS-CoV-2, while 70.9% were negative and 2.95% were inconclusive or invalid. Three peaks of positive tests were observed in November 2020, April 2021, and February 2022. The study selected 92 preserved RNA samples for triplex PCR assay development, validating the primers' specificity and confirming the quality of the nucleic acids. The comparative analysis showed the efficiency and accuracy of the endpoint reverse transcription triplex PCR method (RT-PCR), indicating its potential as a cost-effective alternative to real-time reverse transcription PCR (qRT-PCR) in low-income countries with limited infrastructure for COVID-19 testing. Conclusion: This method has the potential to facilitate large-scale diagnosis of SARS-CoV-2 infections, allowing for rapid and appropriate therapeutic management and ongoing monitoring of patients. Additionally, the method can be easily adapted for the detection of other pathogens. [ABSTRACT FROM AUTHOR]

A healthy, sustainable diet contributes massively to the general well-being of a population. Nowadays, people have started to significantly improve their diet by reducing processed products, as well as including a higher number of fruits, vegetables, cereals, and spices to flavor their food. However, making the right food choice, without any harmful pathogens that pose a risk to human health, can remain quite challenging. Despite prioritizing food safety in its processing, production, and distribution, food contamination remains a prevalent and undesirable occurrence. This study aims to detect the fungal load of commonly used green leaf spices commercialized in Romania and the impact of those microorganisms and their secondary metabolites on consumers. Six (28.57%) out of the twenty-one tested samples showed different degrees of fungal contamination, mostly with Aspergillus section Flavi, followed by Aspergillus section Nigri and other fungi in lower amounts. Three main fungal secondary metabolites with potential impact on consumers, namely mycotoxins, were determined with high-performance liquid chromatography (HPLC): Aflatoxin B1, Ochratoxin A, and Zearalenone. Moreover, their legal limits (5 μg/kg, 15 μg/kg, and 50 μg/kg, respectively) were exceeded by 95.24%, 100%, and 85.71%, respectively. Environmental factors that affect the processing and packaging of these spices did not show any relation to fungal contamination, conversely to price, which significantly correlates with the mycological quality of the products. [ABSTRACT FROM AUTHOR]